Plastics socket arrangement for objective lenses with distance adjustment for cameras

ABSTRACT

An improved plastic-produced fitting of special construction of objective lenses of cameras with distance adjustment, simplifying the production and avoiding lathe-work, milling, boring a.s.o. but being instantly ready for assembly and a process of mounting and demounting for it.

United States Patent ssrncir noou' [72] Inventors Karl Heinz LangeEnnigloh; Karl Tacke, Gohleld-Blscholshagen, both of Germany [2]] Appl.No. 831,067

[22] Filed June 6, I969 [45] Patented Dec. 7, I971 [73 Assignee BaldaWerke Photographische Gerate und Kunststolt R. GruterKomrnandltgesellschatt Bunde. Westphalia, Germany [32] Priority Aug. 8,1968 [3 3 Germany [Bl] P17970513 [54] PLASTICS SOCKET ARRANGEMENT FOROBJECTIVE LENSES WITH DISTANCE ADJUSTMENT FOR CAMERAS 11 Claims, 6Drawing Figs.

52 user [51] Int. Cl G'02b 7/02 [50] Field of Search 350/252. 253, 256,257

[56] References Cited UNITED STATES PATENTS 2.853.925 9/1958 Lee 350/2522,707,418 5/1955 Magnuson 350/252 Primary ExaminerDavid SchonbergAssistant Examiner-Michael J. Tekar Attorney-Sparrow and SparrowABSTRACT: An improved plastic-produced fitting of special constructionof objective lenses of cameras with distance adjustment, simplifying theproduction and avoiding lathe-work, milling, boring a.s.o. but beinginstantly ready for assembly and a process of mounting and demountingfor it.

PATENTED 'DEC 7 I971 SHEET 2 BF 3 Aw r nwa PLASTICS SOCKET ARRANGEMENTFOR OBJECTIVE LENSES WITH DISTANCE ADJUSTMENT FOR CAMERAS BACKGROUND OFTHE INVENTION This invention relates to fittings for objective lenses incameras with distance adjustment and to improvements in such fittings inparticular pertaining mainly to simplified assembly means by which aneasier assembly working process for the camera is attained in view offormer constructions.

It is known to mount camera lenses in the camera by means of screws andsimilar means and arrangements. But this is expensive and assiduous.Lenses without adjusting possibility have already been riveted or weldedbut apart from the missing of distance adjusting the riveting or weldingprocess also is expensive.

SUMMARY It is an object of the present invention to overcome thementioned disadvantages and difficulties and to provide an improvedconstruction consisting of two fitting parts the one of whichsurrounding the other concentrically, the inner one serving as theactual lens supporting part and having a cylindrical fitting surface andabutment for a precise reception of a lens or double lens. On the outersurface this part is provided with a thread of the camera front part forthe distance adjusting of the lens and furthermore provided with afitting cylinder which is axially profiled on which cylinder the otherpart in the form of an outer fitting part provided with engaging nosesfor the profiled fitting surface can be shifted as an operating ring ina desired position of the lens, adapted to the associated objectdistance. This operating ring is provided with resilient resting orcatching noses which in the desired rotary position of the true lensfitting in view of the operating ring engages a resting face of theinner fitting part and thereby firmly secures the mutual rotary positionand effects the forceand formlocking connection.

Various further and more specific purposes, features and advantages willclearly appear from the detailed description given below taken inconnection with the accompanying drawings which form part of thisspecification and illustrate merely by way of example embodiments of thedevice of the invention.

BRIEF DESCRIPTION OF DRAWING In the following description and in theclaims, parts will be identified by specific names for convenience, butsuch names are intended to be as generic in their application to similarparts as the art will permit. Like reference characters denote likeparts in the several figures of the drawings, in which FIG. I shows inenlarged scale (:l) a section of the true lens fitting part withindicated lens and lens clamping ring,

FIG. 2 is a view of the part according to FIG. 1 in direction of arrowll of FIG. 1,

FIG. 3 is a cross section of the operating ring partly as a view,

FIG. 4 is in a somewhat smaller scale (2: l the inner view of theoperating ring,

FIG. 5 is the outer view of the operating ring,

FIG. 6 shows the lens supporting part and the operating ring at thestart of the assembly process just prior to the assembling of the twoparts.

DESCRIPTION In the Figures, there is a lens supporting part or socketwith a usual grooved light entrance hopper 2, additionally serving as afitting cylinder and at its outer cylindrical surface being providedwith axial ribs 3 and thereby created grooves 4. Supporting part 1contains a lens fitting surface 5 and abutting surface 50 for a correctreception of a lens or double lens 6, secured by a clamping ring 7 whicheither is inserted with friction or rests by means of a bead 8. Insteadof this or additionally also an adhesive lump or spot 9 for securingring 7 may be used. The clamping ring 7 is embraced by a bushinglikepart 10 which through a recess 11 changes over into an outer ring 12which at its circumference-is provided with an adjusting thread I3engaging a corresponding inner thread 14 which can be screwed into acylindrical socket I5 which may be integral with the camera front wallI6.

The FIGS. 3, 4 and 5 show the operating ring 17. It coinprises a innercylindrical part 18 (FIG. 4) which at four points of its circumferenceis provided with double recesses 19 leav ing between each pair ofrecesses a resilient tongue 20, which at its free end is provided withan inwardly protruding lockingnose 21 (FIG. 3), on the oblique entrancesurfaces 22 each of which having furthermore an auxiliary guiding andlocking nose 23, the width of which in circumference direction is sodimensioned that it fits conveniently in one of the grooves 4 of thelens supporting part 1. Two additional inwardly directed noses 24associated to each of the resilient tongues engage, if locking noses 23are introduced, engage grooves 4 of lens supporting part I. The outercylindrical part, that is operating ring 17, has furthermore an outercylindrical part 25 serving as a handle and near its front side providedwith gripping noses 26. Between inner cylindrical part 18 and outersocket 25 there is a cylindrical recess 27 into which protrudes a singleabutting nose 28 of the outer cylindrical part 25. The recess 27 servesthe purpose of saving material as well as of receiving the preferablyintegral screw socket 15 of the camera front wall 16 and of covering thelatter. Integral with the otherwise smooth front side of the screwsocket 16 are two further abutting noses 29 and 30 between which thenose 28 fits loosely. The adjusting area of lens 6 therefore is limitedaccording. A resting surface 31 is arranged for engagement with lockingnoses 21 (FIG. 1).

Referring now to FIG. 6, there is mounting effected in such manner thatat first lens 6 is placed into the clamping ring 7 and together with thelatter is shifted into lens supporting part 1 so that clamping ring 7either rests at 8 by friction or is maintained in its final position bya glue spot 9, The lens supporting socket part 1 is screwed by means ofthe adjusting thread 13 into the cylindrical socket 15 of the camerafront wall 16, especially so far that an optic testing instrument for acertain object-distance adjustment, preferably focused for infinity,shows the right distance of the lens from the film plane. In thisposition the outer socket part, that is, operating ring 17 in FIG. 6 isshifted from the right, the fixing noses 23 of the resilient tongues 20are sliding on the oblique surface 22 searching automatically theengagement of one of the grooves 4, and there each one of the furthernoses 24 of inner cylindrical socket 18 associated to the tongues 20enters also a groove of inner cylindrical part 1. Operating ring 17 atthis operation will be held so that the abutment 28 is situated close tothe one abutting nose 29 of the cylindrical socket 15 while the otherabutting nose 30 limits the clearance of lens supporting part 1. Thenecessary setting of operating ring 17 during the insertion thereof isfacilitated by corresponding symbols 32 (for landscape) and 33 (for agroup of persons) corresponding to abutments 29 and 30 and situated atthe front side 34 or at the circumference of operating ring 17, smallangle difierences being irrelevant because of being within the allowedtolerance. The abutment 29 in this embodiment is situated in the centerof the landscape symbol and at insertion in the front view to the leftclose to the abutment 29 of cylindrical socket 15. As soon as fixingnoses 23 and noses 24 have entered the grooves 4, the relative rotaryposition between parts 1 and 17 is defined and further does not have tobe observed except that the abutment must be situated between theabutments 29, 30 of the camera front wall 18. If now operating ring 17is fully shifted on,

rigidly and operably connected together because in view of r the factthat abutment 28 of the operating ring is situated between abutments 29and 30 of the camera front wall 18 and therefore in view of the limitedrotary range and locking connection of lens supporting part 1 andoperating ring 17, the former cannot be screwed out.

The dismantling of parts 1, l6, 17 during a necessary repair may beeffected by a special tool provided with two pins 35, the latter beinginserted from behind into corresponding openings 36 of the camera frontwall 18 when said front part is removed. By pressing at the ring surface37 of operating ring 17 the resilient tongues 20 with resting noses 21are forced to yield resiliently so that operating ring 17 can beremoved.

What we claim is: cm 1. Lens mounting device for an objective of acamera, said camera having a front part, said device having distanceadjustment means, said device comprising an axially symmetric lenssupporting part having a cylindrical fitting surface for fitting of saidlens, said supporting part having a distance focusing thread, an outeraxially grooved fitting cylinder and a resting surface disposed at oneend of said fitting cylinder, as female thread on said front part ofsaid camera, said female thread engaging said distance focusing threadand securing adjustably said supporting part of said lens on said frontpart of said camera, an operating ring having an inner cylindricalfitting surface, said fitting surface having a plurality of both axiallyand radially extending engaging noses and having a plurality ofresilient locking noses, said fitting surface of said operating ringembracing said axially grooved fitting cylinder and said resting surfaceof said supporting part of said lens, said engaging noses engaging saidgrooves of said fitting cylinder in a desired relative position of saidoperating ring, said supporting part of said lens and said locking nosesengaging said resting surface for preventing said operating ring frombeing retracted from said supporting part of said lens without a tool,and an abutment on said operating ring and corresponding counterabutments on said front part of said camera, said counter abutmentsdisposed for limiting the range of movement of said abutment on saidabutment ring according to said distance adjustment of said operatingring.

2. Device according to claim 1, and a substantially tubular sectionhaving a substantially hopper-shaped light-entering opening on saidsupporting part of said lens at said front part of said camera, saidtubular section having an outer surface constituting said axiallygrooved fitting cylinder and having said resting surface on saidcylinder directed toward said camera.

3. Device according to claim 2, said locking noses, said engaging nosesand said fitting surface being integrally formed with said operatingring.

4. Device according to claim 3, and two concentrically arrangedcylindrical parts on said operating ring, said parts consisting of anouter cylindrical part and an inner cylindrical part, and an annularfront side section on said operating ring, said annular front partintegrally connecting said cylindrical parts, said outer surface of saidouter cylindrical part serving as a handle and said inner surface ofsaid inner cylindrical part serving as said cylindrical fitting surfaceof said operating ring, said inner cylindrical part having doublerecesses and resilient tongues disposed between the two recesses of saiddouble recesses, each one of said tongues extending axially of saidinner cylindrical part and having one of said locking noses thereon,said locking noses engaging said resting surface of said supporting partof said lens, and said inner cylindrical part of said operating ringhaving said engaging noses thereon, said engaging noses engaging saidgrooves of said axially grooved fitting cylinder of said supporting partof said lens. 5. Device according to claim 4, and a cylindrical socketon said front'part of said camera, said socket being disposedconcentrically of the optical axis of said objective of said camera,said socket having said female thread thereon engaging said focusingthread of said supporting part of said lens, and said socket beingcovered by being surrounded by said outer cylindrical part of saidoperating ring after the finished assembly of said device.

6. Device according to claim 5, said socket on said front part of saidcamera havin said counter abutments disposed at the outer surface ofsaid ront part, and said inner surface of said outer cylindrical part ofsaid operating ring being provided with said abutment cooperating withsaid counter abutments.

7. Device according to claim 6, and distance symbols on said operatingring, said symbols associated to each one of said counter abutments onsaid cylindrical thread socket, and reading marks in the end positionsof said abutment of said operating ring, said symbols meeting with saidmarks thereby indicating the adjusted distance range.

8. Device according to claim 7, and hopper-shaped distributed obliqueinsert surfaces on said resilient locking noses, each one ofsaid-surfaces having an integral auxiliary leading nose thereon, saidleading noses being disposed for being shifted into a groove of saidaxially grooved fitting cylinder of said supporting part of said lens atthe start of the assembly of said objective of said camera.

9. Device according to claim 8, said lens supported by said supportingpart thereof being fixedly attached by a glue spot in said cylindricalfitting surface.

10. Device according to claim 8, and a clamping ring being disposed forholding said lens by an over dead center engagement.

11. Device according to claim 4, said device substantially consisting ofprecision-molded plastic parts.

i i l II i ran!

1. Lens mounting device for an objective of a camera, said camera havinga front part, said device having distance adjustment means, said devicecomprising an axially symmetric lens supporting part having acylindrical fitting surface for fitting of said lens, said supportingpart having a distance focusing thread, an outer axially grooved fittingcylinder and a resting surface disposed at one end of said fittingcylinder, a female thread on said front part of said camera, said femalethread engaging said distance focusing thread and securing adjustablysaid supporting part of said lens on said front part of said camera, anoperating ring having an inner cylindrical fitting surface, said fittingsurface having a plurality of both axially and radially extendingengaging noses and having a plurality of resilient locking noses, saidfitting surface of said operating ring embracing said axially groovedfitting cylinder and said resting surface of said supporting part ofsaid lens, said engaging noses engaging said grooves of said fittingcylinder in a desired relative position of said operating ring, saidsupporting part of said lens and said locking noses engaging saidresting surface for preventing said operating ring from being retractedfrom said supporting part of said lens without a tool, and an abutmenton said operating ring and corresponding counter abutments on said frontpart of said camera, said counter abutments disposed for limiting therange of movement of said abutment on said abutment ring according tosaid distance adjustment of said operating ring.
 2. Device according toclaim 1, and a substantially tubular section having a substantiallyhopper-shaped light-entering opening on said supporting part of saidlens at said front part of said camera, said tubular section having anouter surface constituting said axially grooved fitting cylinder andhaving said resting surface on said cylinder directed toward saidcamera.
 3. Device according to claim 2, said locking noses, saidengaging noses and said fitting surface being integrally formed withsaid operating ring.
 4. Device according to claim 3, and twoconcentrically arranged cylindrical parts on said operating ring, saidparts consisting of an outer cylindrical part and an inner cylindricalpart, and an annular front side section on said operating ring, saidannular Front part integrally connecting said cylindrical parts, saidouter surface of said outer cylindrical part serving as a handle andsaid inner surface of said inner cylindrical part serving as saidcylindrical fitting surface of said operating ring, said innercylindrical part having double recesses and resilient tongues disposedbetween the two recesses of said double recesses, each one of saidtongues extending axially of said inner cylindrical part and having oneof said locking noses thereon, said locking noses engaging said restingsurface of said supporting part of said lens, and said inner cylindricalpart of said operating ring having said engaging noses thereon, saidengaging noses engaging said grooves of said axially grooved fittingcylinder of said supporting part of said lens.
 5. Device according toclaim 4, and a cylindrical socket on said front part of said camera,said socket being disposed concentrically of the optical axis of saidobjective of said camera, said socket having said female thread thereonengaging said focusing thread of said supporting part of said lens, andsaid socket being covered by being surrounded by said outer cylindricalpart of said operating ring after the finished assembly of said device.6. Device according to claim 5, said socket on said front part of saidcamera having said counter abutments disposed at the outer surface ofsaid front part, and said inner surface of said outer cylindrical partof said operating ring being provided with said abutment cooperatingwith said counter abutments.
 7. Device according to claim 6, anddistance symbols on said operating ring, said symbols associated to eachone of said counter abutments on said cylindrical thread socket, andreading marks in the end positions of said abutment of said operatingring, said symbols meeting with said marks thereby indicating theadjusted distance range.
 8. Device according to claim 7, andhopper-shaped distributed oblique insert surfaces on said resilientlocking noses, each one of said surfaces having an integral auxiliaryleading nose thereon, said leading noses being disposed for beingshifted into a groove of said axially grooved fitting cylinder of saidsupporting part of said lens at the start of the assembly of saidobjective of said camera.
 9. Device according to claim 8, said lenssupported by said supporting part thereof being fixedly attached by aglue spot in said cylindrical fitting surface.
 10. Device according toclaim 8, and a clamping ring being disposed for holding said lens by anover dead center engagement.
 11. Device according to claim 4, saiddevice substantially consisting of precision-molded plastic parts.